Spinal Cord and Spinal Nerves

Question 1

Gray matter consist of:

Answer 1

mainly of neuronal cells bodies– divided into the dorsal horn, ventral horn, and lateral horn

Question 2

White matter consist of:

Answer 2

mainly of neuronal fibers– divided into the dorsal funiculus, ventral funiculus, and lateral funiculus

Question 3

Ventral Median Fissure

Answer 3

a distinct surface indentation present at all spinal cord levels and is related to the anterior spinal artery

Question 4

Dorsal Median Fissure

Answer 4

a less distinct surface indentation present at all spinal cord levels

Question 5

Dorsal Intermediate Septum

Answer 5

A surface indentation present only at and above T6 that distinguishes ascending fibers within the graciel fasciculus from ascending fibers within the cuneate fasciculus

Question 6

conus medullaris

Answer 6

the end of the spinal cord, which occurs at vertebral level L1 in the adult and vertebral level L3 in the newborn

Question 7

Cauda Equina

Answer 7

consists of the dorsal and ventral nerve roots of L2 through coccygeal 1 spinal nerves traveling in teh subarachoid space below the conus medullaris

Question 8

Filum terminale

Answer 8

prolongatino of the pia mater from teh conus medullaris to the end of the dural sac at vertebral level S2 where it blends with the dura. Tha dura continues caudally as the filum of the dura mater, which attaches to the dorsum of the coccyx bone

Question 9

The space in which contain fat and the internal vertebral venous plexus

Answer 9

Epidural Space

Question 10

List 31 pairs of spinal nerves

Answer 10

8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal

Question 11

The four functional components of a spinal nerve

Answer 11

general somatic afferent (GSA), general somatic efferent (GSE_, general visceral afferent (GVA), ad general visceral efferent (GVE)

Question 12

The muscle stretch reflex includes

Answer 12

the neuromuscular spindle, GSA dorsal root ganglion cell, GSE ventral horn gamma motor neuron, and the neuromuscular junction

Question 13

Describe Lumbar puncture

Answer 13

Can be done to either withdraw CSF or inject an anesthetic; needle inserted either below or above the spinous process of the L4 vertebra; start from skin - superficial fascia - supraspinous ligament - interspinous ligament - ligamentum flavum - epidural space containing the internal vertebral venous plexus - dura mater - arachnoid - subarachnoid space containing CSF. The pia mater is not pierced.

Question 14

Spinal anesthesia is produced by injecting anesthetic into which area? What happen?

Answer 14

the subarachnoid space; it produces anesthesia of the erineum, pelvic floor, and birth canal, along WITH the elimination if the sensation of uterine contractions and loss of motoe and sensory functions of the lower limbs

Question 15

Sensory nerve fibers for pain from the uterus travel with the following nerves:

Answer 15

• Pelvic splanchnic nerves (parasympathetic) to S2 to S4 spinal levels from the cervix
• Hypogastric plexus and lumbar splanchnic nerves to L1 to L3 spinal levels from the fundus and body of the uterus and oviducts

Question 16

To block the pain for vaginal childbirth Spinal anesthesia must be up to which spinal nerve? for cesarean section?

Answer 16

Spinal nerve T10; T4

Question 17

Why do pregnant women require a smaller dose of anesthetic?

Answer 17

because the subarachnoid space is compressed because the internal vertebral venous plexus is engorged with blood from the pregnant uterus compressing the inferior vena cava

Question 18

What are complications due to Spinal Anesthesia?

Answer 18

hypotension due to sympathetic blockade and vasolidation, respiratory paralysis involving the phrenic nerve due to high spinal blockade, and spinal headache do to CSF leakage

Question 19

Where do you inject to produce Lumbar Epidural Anesthesia?

Answer 19

epidural space above or below the spinous process of the L4 vertebra OR (in case of participatory childbirth) inject into the epidural space of the sacral canal either through the sacral hiatus or the posterior sacral foramina

Question 20

What happen in Lumbar Epidural Anesthesia?

Answer 20

The anesthetic will act upon S2-coccygeal 1 spinal nerves of the cauda equina producing anesthesia of the perineum, pelvic floor, and birth canal WITHOUT the eliminatino of sensation of the uterine contractions and loss of motor and sensory functions of the lower limbs

Question 21

What are possible complications in Lumbar Epidural Anesthesia?

Answer 21

Respiratiry paralysis due to high spinal blockage; central nervous system (CNS) toxicity (slurred speech, tinnitus, convulsions, cardiac arrest) die to injection of the anesthetic into the internal vertebral venous plexus

Question 22

Syringomyelia

Answer 22

a chronic progressive disease in which longitudinal cavities form in the cervical region of the spinal cord. This characteristically results in wasting of the muscles in the hands and a loss of sensation.

Question 23

Chordomas

Answer 23

a malignant tumor arising from the embryonic remains of the notochord.

Question 24

Paraplegia

Answer 24

transection anywhere between the cervical and lumbar enlargements of the spinal cord (paralysis of lower limbs)

Question 25

Quadriplegia

Answer 25

transection above C3. These individuas may die quickly due to respiratory failure if the phrenic nerve is compromised (paralysis of all four limbs)

Question 26

List any complications of SCI (Spinal cord injury); What medicine can you use to help?

Answer 26

hypotension in the acute setting, ileus, renal stones, pyelonephritis, renal failure, and deep venous thrombosis; Methylprednisolone (within 8 hours injury)

Question 27

Astrocytomas

Answer 27

a tumor composed of astrocytes; the most common type of primary brain tumor and also found throughout the central nervous system

Question 28

Meningiomas

Answer 28

a benign, slow-growing tumor of the meninges, usually next to the dura mater, which may invade the skull or cause hyperostosis, and often causes increased intracranial pressure

Question 29

Schwannomas

Answer 29

a neoplasm originating from Schwann cells (of the myelin sheath) of neurons; schwannomas include neurofibromas and neurilemomas.